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arXiv · 1303.3846

Ambipolar Surface Conduction in Ternary Topological Insulator Bi_2(Te_{1-x}Se_x)_3 Nanoribbons

ZhenHua Wang·Richard L. J. Qiu·Chee Huei Lee·ZhiDong Zhang·Xuan P. A. Gao
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Abstract

We report the composition and gate voltage induced tuning of transport properties in chemically synthesized Bi2(Te1-xSex)3 nanoribbons. It is found that increasing Se concentration effectively suppresses the bulk carrier transport and induces semiconducting behavior in the temperature dependent resistance of Bi2(Te1-xSex)3 nanoribbons when x is greater than ~10%. In Bi2(Te1-xSex)3 nanoribbons with x ~20%, gate voltage enables ambipolar modulation of resistance (or conductance) in samples with thickness around or larger than 100nm, indicating significantly enhanced contribution in transport from the gapless surface states.

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ZhenHua Wang, Richard L. J. Qiu, Chee Huei Lee, ZhiDong Zhang, Xuan P. A. Gao. 2013-03-15. Ambipolar Surface Conduction in Ternary Topological Insulator Bi_2(Te_{1-x}Se_x)_3 Nanoribbons. https://doi.org/10.1021/nn304684b

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